Buckle



Jan. 11, 1955 P. w. WHITE 2,698,980

BUCKLE Filed Aug. 4, 1951 2 Sheets-Sheet 1 I Hy n.

Jgy PM Cain/v2.65;

, Jan. 11, 955 P. w. WHITE 2,698,980

BUCKLE Filed Aug. 4, 1951 2 Sheets-Sheet 2 INVENTOR.

Feud W W/wic BY United States Patent BUCKLE Paul W. White, New Haven, Conn.

Application August 4, 1951, Serial No. 240,343

9 Claims. (Cl. 24-194) This invention relates to buckles, more particularly to slide buckles adapted to be mounted on straps, bands, or the like, for detachably securing garments or other articles, and the invention has for an object the provision of a slide buckle which may be readily stamped from sheet metal, is inexpensive to manufacture, and is effective to clamp firmly or release readily a strap or the like.

The invention, while applicable to slide buckles generally, is particularly useful in connection with and constitutes improvements in buckles of the type disclosed in prior Patents No. 2,361,895, issued October 31, 1944, and No. 2,334,462, issued November 16, 1943, to Paul W. White, and No. 2,549,735, issued April 17, 1951, to Paul W. White and Joseph J. Schutz. In many instances slide buckles of the above type are secured to the suspender or garter strap by threading the strap end around a strap attaching cross-bar on the buckle frame, turning the strap end over to form a loop and closing the loop by sewing or otherwise securing the strap end to the strap. Thereafter the free end of the strap is threaded through the cross-bars of the buckle in the conventional manner. It is customary for the buckle frame and slide to be assembled before shipment to the manufacturer of the article on which the buckle is to be used. For example, in the manufacture of suspenders the slide buckle is completely assembled and shipped in this condition to the suspender manufacturer. As a result the suspender manufacturer is called upon to provide sufficiently skilled personnel to thread the end of the suspender strap through the buckle and sew the loop thereon. It has been found that such a procedure is inherently time consuming and laborious and requires relatively skilled labor to produce a satisfactorily uniform product.

Accordingly, it is a further object of the present invention to provide an improved slide buckle which is particularly adapted for use as a suspender or garter buckle and presents a neat and attractive appearance, which may be readily formed from sheet metal by a simple stamping operation, which is adapted for shipment unassembled to the article manufacturer and which may thereafter be quickly and economically assembled by relatively unskilled personnel, and wherein the tolerances on the buckle dimensions may be relatively large.

According to one aspect of the invention a slide buckle is provided comprising a frame having side-bars and cross-bars defining a strap receiving opening therethrough to receive a strap. The edges of the frame side-bars are inturned to provide slide supporting shoulders and the buckle slide consists of a single cross-bar having end portions adapted for sliding movement along said shoulders and an inclined plane strap engaging portion inclined relative to said end portions for cooperation with one of said frame cross-bars to clamp in adjusted position a strap threaded through said opening. The single cross-bar slide is provided with a clamping portion which is turned under the inclined plane portion thereof to grip the end of the strap so that the slide may be secured to the end of a suspender strap after shipment to the suspender manufacturer by automatic machinery and with a minimum of time and labor consumed.

A second one of the frame cross-bars is provided with a lug portion extending into the path of movement of the strap engaging portion of said slide to limit relative movement between said slide and said frame in one direction and said one frame cross-bar is provided with a flanged edge extending into the path of movement of Patented Jan. 11, 1955 the strap engaging portion of said slide to limit relative movement of said slide and said frame in the opposite direction. A third one of said frame cross-bars forms a strap hold-down bar and is positioned outside the path of movement of the strap engaging portion of the slide. The second frame cross-bar is deformable upwardly to permit insertion of the slide within the frame after the suspender strap has been secured thereto by merely sliding the strap engaging portion thereof past th strap hold-down cross-bar and forcing the inclined plane portion thereof past said lug portion in the direction of said one frame cross-bar. With this arrangement the suspender or garter manufacturer merely snaps the slide into place within the buckle frame after the suspender strap is secured to the slide by a simple stamping operation and the cost of assembling the suspender strap and buckle is greatly reduced.

In accordance with an alternative embodiment of the invention, the lug portion on the second frame crossbar is spaced from said one frame cross-bar by an amount sufficient to permit the insertion of the slide within said frame, after the suspender strap is clamped thereto, by positioning the slide cross-bar ahead of the lug portion and at such an angle that the end portions thereof clear said slide supporting shoulders and thereafter twisting the slide until said end portions are retained beneath said shoulders with said slide cross-bar transverse thereto.

For a more complete understanding of the invention reference should now be had to the drawings in which:

Fig. 1 is a top plan view of a buckle frame adapted for use in buckles embodying the present invention;

F Fig. 2 is a bottom plan view of the frame shown in Fig. 3 is a top plan view of a slide adapted for cooperation with the frame shown in Figs. 1 and 2;

Fig. 4 is a left-hand end view of the slide of Fig. 3;

Fig. 5 is a right-hand end view of the slide of Fig. 3;

Fig. 6 is a side view of the slide of Fig. 3 showing the manner in which the end of a strap is clamped therein;

Fig. 7 is a longitudinal sectional view showing the frame and slide in assembled relation with a strap partially threaded therethrough;

Fig. 8 is a sectional view similar to Fig. 7, but showing the buckle and strap in clamping relation;

Fig. 9 is a bottom plan view of the frame and slide showing the manner in which the slide is inserted within the buckle frame; and

Figs. 10, 11, and 12 are longitudinal sectional views of an alternative embodiment of the invention showing the manner in which the frame and slide thereof are assembled.

Referring now to the drawing, the invention is shown as comprising a suspender buckle including a sheet metal frame 10 (Figs. 1 and 2) which may be conveniently and economically formed by a simple stamping operation, and a sheet metal slide 11 (Figs. 3, 4, 5, and 6) which may be formed by a similar stamping operation and which is adapted to cooperate with the frame 10. As shown, the frame 10 comprises a pair of side-bars 12 and 13 and a pair of cross-bars 14 and 15, the cross-bars 14 and 15 and the side-bars 12 and 13 forming a suitable strap receiving opening 17 through which a strap may be threaded. In the illustrated embodiment, the frame 10 is provided with a third cross-bar 16 which may be employed as a strap hold-down bar as best shown in Fig. 8.

As shown best in Fig. 2, the side-bars 12 and 13 are provided with rearwardly extending side wall portions 20 and 21 which form a recess suitable for receiving the slide 11. The side wall portions 20 and 21 are provided with the inwardly turned portions 22 and 23 which extend along the side-oars 12 and 13 and rearwardly of the face of the buckle frame to provide slide supporting runners or shoulders. The center cross-bar 14 of the frame 10 is deformed upwardly out of the main plane of the frame, as shown best in Figs. 7 and 8, and there is provided a lug portion 18 intermediate the length of the cross-bar 14 which extends downwardly to form a stop for the slide 11 as will be described in more detail hereinafter.

Referring now to Figs. 3, 4, 5, and 6, the side 11 consists of a single cross-bar 30 having end portions 31 and 32 which are adapted for sliding movement along the shoulders 22 and 23 of the frame 10, and an intermediate inclined plane strap engaging portion 35. The inclined plane portion 35 is formed by deforming the cross-bar upwardly at points 36 and 37 adjacent the end portions 31 and 32, and deforming the cross-bar downwardly at points 38 and 39 also adjacent the end runner portions 31 and 32 of the slide cross-bar 30. As shown best in Fig. 6, by deforming the cross-bar 30 in the manner described above the inclined plane portion is positioned relative to the end portions 31 and 32 so that the lower edge thereof is positioned well below the plane of the end portions 31 and 32 and the upper edge of the inclined plane portion 35 is positioned slightly above the plane of the end portions 31 and 32.

In order to secure the end of a strap to the slide 11, the bottom edge of the slide cross-bar 30 is turned inwardly under the inclined plane portion 35 thereof to provide a strap end clamping portion 42 which is positioned rearwardly of the strap engaging portion 35 and extends generally parallel thereto. The strap end clamping portion 42 is provided with the projections or tines 43 and 44, which are struck out from the portion 42 and which aid in clamping the end of a strap between the portions 35 and 42 as described in more detail hereinafter. As clearly shown in Fig. 4, the strap end clamping portion 42 is formed to follow the contour of the inclined plane strap engaging portion 35. Thus the portion 42 is tapered inwardly to conform to the raised portions 36 and 37 formed in the manner described above. With this arrangement the portions 35 and 42 may be tightly pressed together and a firm, reliable grip on the end of the strap is obtained.

Before the slide 11 is assembled in the frame 16 it is necessary securely to clamp the end of a strap, such as a suspender strap or the like, in the slide 11. More particularly, and as clearly shown in Fig. 6, one end of a strap 50 is positioned between the portions 35 and 42 of the slide cross-bar 30 and these portions are compressed together so that the tines 43 and 44 on the portion 42 enter the webbing of the strap and the strap end is securely held between these portions of the slide crossbar 30. With this arrangement the slide 11 and frame may be shipped separately to the suspender manufacturer and the slide may be assembled onto the end of a suspender strap by means of automatic machinery thereby greatly reducing the cost of this phase of the assembly of conventional buckle and strap arrangements.

With one end of a strap securely fixed to the slide cross-bar in the manner described above, it is then necessary to assemble the slide 11 in the frame 10. In order to assemble the slide 11 in the frame 10 by a simple and economical procedure which may be practiced by relatively unskilled personnel and in a minimum of time, the slide 11 is positioned with the upper edge of the inclined plane portion thereof ahead of but adjacent the lug portion 18 on the frame cross-bar 14 and with the end runner portions 31 and 32 thereof clearing the edges of the slide supporting shoulders 22 and 23 of the frame 10. Since the cross-bar 14 is deformed upwardly from the main plane of the buckle frame it will be evident that the slide cross-bar 30 may be inserted into the frame by a sufficient amount to position the end portions 31 and 32 thereof inside of the slide supporting shoulders 22 and 23. The slide 11 is then rotated in the direction of the arrow 51, as shown in Fig. 9, and about the lug 18 so that the end portions 31 and 32 are positioned beneath and retained within the slide supporting shoulders 22 and 23.

As clearly shown in Fig. 7 of the drawings, the slide cross-bar 11 is thereafter retained within the frame 10 by virtue of the fact that the lug portion 18 extends downwardly into the path of movement of the inclined plane strap engaging portion 35 to limit relative movement between the slide and frame in one direction, and the forward cross-bar 15 of the frame 10 also extends into the path of movement of the strap engaging portion 35 to limit relative movement between the slide and frame in the opposite direction. It will be noted that the lug portion 18 is spaced from the rear edge of the frame cross-bar 15 by an amount sufficient to permit the slide 11 to be twisted sufliciently to permit insertion and removal of the slide from beneath the slide supporting shoulders 22 and 23 in the manner described above.

Accordingly, the slide 11 is retained within the frame 10 during normal usage of the buckle although these members may be quickly assembled and disassembled in accordance with the procedure outlined above.

Once the slide and frame have been assembled the operation of the buckle thereby produced is in general similar to the operation set forth in the above identified prior patents. Thus, the slide 11 is moved away from the frame cross-bar 15 to permit threading of a strap through the strap receiving opening 17 in the frame 10 as shown in Fig. 7, and the cross-bar 15 on the frame 10 in cooperation with the inclined portion 35 of the slide cross-bar 11 serves to clamp the strap in adjusted positions in the buckle whenever tension is applied.

In Figs. 7 and 8 the buckle is shown in connection with a suspender strap 54 having an end portion 55 which is securely clamped in the slide cross-bar 30 in the manner described above. From this clamped end the strap 54 extends in the direction of the arrow 56 in Fig. 8 to form the usual adjustable suspender loop and is then threaded between the cross-bars 11 and 15, over the cross-bar 14 and then under the bar 16 from which point the strap 54 extends in the indicated direction over the shoulder of the wearer in the usual fashion. In Fig. 7 the buckle is shown with the frame 10 and slide 11 in partially threaded position with the free end of the strap 54 extending through the strap receiving opening 17. When tension is applied to the strap the slide cross-bar 11 is moved in a left-hand direction from the position shown in Fig. 7 to the position shown in Fig. 8, in which position the strap is firmly clamped between the cross-bar 15 on the frame 10 and the inclined plane strap engaging portion 35 of the slide 11.

It will be noted that the clamped end 55 of the strap 54 is doubled back over the strap end clamping portion 42 of the slide 11 so that substantially all portions of the buckle are covered and no metallic parts are exposed. Furthermore, the inclined plane portion 35 is so correlated in height and location relative to the inner edge of the cross-bar 15 as to provide an effective clamping angle between these members such that the strap 54 is securely clamped therebetween and may be readily released as desired. In this connection it will be understood that the strap 54, which is conventionally of fabric, elastic webbing, or other resilient material, becomes wedged beneath the inner edge of the clamping bar 15 by virtue of the inclined plane nature of the portion 35 so that a reliable and effective clamping action is obtained so long as tension is applied to the strap. HoW- ever, upon release of tension the elastic material seeks to return to its normal condition and automatically overcomes the wcdge-like grip so that the buckle can be readily readjusted.

As clearly shown in Figs. 7 and 8, the strap end 55 is securely clamped against the underside of the inclined portion 35 of the single cross-bar slide 11 by means of the inturned portion 42 thereof. Furthermore, the tines 43 and 44 are struck out of the portion 42 in such a direction as further to prevent the strap end 55 from being pulled out of the slot formed between the portions 35 and 42. Thus, as tension is applied to the strap end 55 in the direction of the arrow 56, shown in Fig. 8, the tines 43 and 44, together with the snubbing action produced at the upper edge of the clamping portion 42, insure that the strap end 55 is not pulled out of the slide 11. With this arrangement an extremely simple and effective cross-bar slide is provided, the inclined plane portion of which serves the dual purpose of clamping the free end of the strap between the upper surface thereof and the frame cross-bar 15, and of cooperating with the strap end clamping portion 42 to clamp the end of the strap 54 against the bottom surface thereof.

In the alternative embodiment of the invention shown in Figs. l0, l1, and 12, the buckle frame 10 and slide 11 are somewhat modified to permit a somewhat simpler assembly of the slide 11 within the frame 10 by forcing the slide past the projecting lug portion 18 on the center cross-bar 14 of the frame 10. As shown in Fig. 10 the inclined plane portion 35 of the slide 11 is formed relative to the end runner portions 31 and 32 thereof so that the inclined portion 35 is substantially entirely below the upper surface of the runners 31 and 32. With this construction it is possible to fit the end portions 31 and 32 beneath the slide supporting shoulders 22 and 23 and slide the inclined plane portion 35 thereof into the ligckle frame from the rear and past the hold-down bar In the construction of Fig. the projecting lug portion 18 on the cross-bar 14 extends downwardly below the main plane of the frame so as to be positioned in the path of the inclined plane portion 35. The slide 11 is then moved in the direction of the arrow shown in Fig. 10 so that it is forced into engagement with the lug portion 18. Due to the resilient nature of the cross-bar 14 and the cross-bar 11 the lug portion 18 is cammed upwardly along the inclined plane portion 35 until the upper edge of the inclined plane portion passes beneath the lug 18, at which time the parts snap back into the position shown in Fig. 11 in which the lug 18 forms a stop for the slide 11 and prevents the slide from being withdrawn in the reverse direction.

As clearly shown in Fig. 11, the clamping bar is provided with a flanged inner edge 60 which extends into the path of movement of the inclined plane portion 35 to prevent the slide from being withdrawn from the frame 10 in the forward direction. The end 55 of a strap 54 is clamped between the portions 35 and 42 of the slide 11 in the manner described above and the strap is threaded through the frame of the buckle as shown in Figs. 11 and 12, and is clamped in adjusted positions between the inclined plane portion 35 and the flanged edge 60 of the cross-bar 15 when tension is applied to the strap, as clearly shown in Fig. 12.

It will be noted that in the embodiment of Figs. 10, 11, and 12 the edge of the strap end clamping portion 42 of the slide 11 is provided with an inturned flange 61 which cooperates with the upper edge of the inclined plane portion 35 thereof securely to retain the strap end 55 within the slide 11. Preferably the flanged edge 61 is notched or serrated to increase the gripping action thereof. With this arrangement the tines 43 and 44 (Fig. 6) are not required, although an effective snubbing action is obtained due to the inturned flange portion 61.

While particular embodiments of this invention have been shown, it will be understood, of course, that the invention is not limited thereto since many modifications may be made, and it is contemplated, therefore, by the appended claims, to cover any such modifications as fall within the true spirit and scope of this invention.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1. A slide buckle comprising, a frame having side-bars and cross bars defining a strap receiving opening therethrough to receive a strap, means on said frame side-bars defining inwardly turned slide supporting shoulders, a single cross-bar slide having end portions positioned in the plane of said frame and retained within said frame for sliding movement along said shoulders and an intermediate strap engaging portion inclined relative to said end portions for cooperation with one of said frame cross-bars to clamp in adjusted position a strap threaded through said opening, the other of said frame cross-bars having a projecting lug intermediate the length thereof and extending rearwardly of the face of said frame, said strap engaging portion extending out of the plane of said end portions to engage said lug in one extreme position of said slide, said slide cross-bar having a strap end clamping portion positioned rearwardly of the strap engaging portion thereof and extending generally parallel thereto for clamping the end of a strap therebetween.

2. A slide buckle comprising, a frame having side-bars and cross-bars defining a strap receiving opening therethrough to receive a strap, said frame side-bars including side walls extending rearwardly of the face of the frame and inwardly turned slide supporting shoulders, a single cross-bar slide having end portions adapted for sliding movement along said shoulders and an intermediate strap engaging portion inclined relative to said end portions for cooperation with one of said frame cross-bars to clamp in adjusted position a strap threaded through said opening, the other of said frame cross-bars being deformed forwardly out of the plane of said frame and having a rearwardly projecting lug intermediate the length thereof, said strap engaging portion extending upwardly out of the plane of said end portions and into the strap receiving opening of said frame to limit relative movement of said slide and frame in one direction by engagement with said lug and in the other direction by engagement with said one frame crossbar, said lug being spaced from said one frame cross-bar by an amount sufficient tto permit insertion of said slide cross-bar within said frame by positioning the slide cross-bar ahead of said projecting lug and at such an angle that the end portions thereof clear said slide supporting shoulders and thereafter turning said slide cross-bar until said end portions are retained within said shoulders and between the side walls of said frame sidebars with said slide cross-bars transverse thereto.

3. A slide buckle comprising, a frame having side-bars and cross-bars defining a strap receiving opening therethrough to receive a strap, said frame side-bars including side walls extending rearwardly of the face of the frame and inwardly turned slide supporting shoulders, a single cross-bar slide having end portions adapted for sliding movement along said shoulders and an intermediate strap engaging portion inclined relative to said end portions for cooperation with one of said frame cross-bars to clamp in adjusted position a strap threaded through said opening, the other of said frame cross-bars being deformed forwardly out of the plane of said frame and having a rearwardly projecting lug intermediate length thereof, said strap engaging portion extending upwardly out of the plane of said end portions and into the strap receiving opening of said frame to limit relative movement of said slide and frame in one direction by engagement with said lug and in the other direction by engagement with said one frame cross-bar, said strap engaging portion having the bottom edge thereof inturned to grip the end of a strap, said lug being spaced from the inner edge of said one frame cross-bar by an amount suflicient to permit insertion of said slide within said frame by positioning the slide cross-bar ahead of said projecting lug and at such an angle that the end portions thereof clear said slide supporting shoulders and thereafter turning said slide crossbar until said end portions are retained within said'shoulders and between the side walls of said frame side-bars with said slide cross-bar transverse thereto.

4. A slide buckle comprising, a frame having side-bars and cross-bars defining a strap receiving opening therethrough to receive a strap, the edges of said frame sidebars being inturned to provide slide supporting shoulders, a single cross-bar slide having end portions adapted for sliding movement along said shoulders and a strap engaging portion inclined relative to said end portions for cooperation with one of said frame cross-bars to clamp in adjusted position a strap threaded through said opening, the other of said frame cross-bars having a lug portion intermediate the length thereof and extending into the path of movement of said strap engaging portion thereby to limit relative movement of said slide and frame in one direction, one edge of said one frame cross-bar having a flange extending into the path of movement of said strap engaging portion to limit relative movement of said slide and frame in the opposite direction, said frame and said slide being sufliciently resilient to permit insertion of said slide within said frame by forcing said inclined strap engaging portion past said lug portion in the direction of said one frame cross-bar.

5. A slide buckle comprising, a frame having side-bars and cross-bars defining a strap receiving opening therethrough to receive a strap, the edges of said frame sidebars being inturned to provide slide supporting shoulders, a single cross-bar slide having end portions adapted for sliding movement along said shoulders and a strap engaging portion inclined relative to said end portions for cooperation with one of said frame cross-bars to clamp in adjusted position a strap threaded through said opening, the other of said frame cross-bars having a lug portion intermediate the length thereof and extending into the path of movement of said strap engaging portion thereby to limit relative movement of said slide and frame in one direction, one edge of said one frame cross-bar having a flange extending into the path of movement of said strap engaging portion to limit relative movement of said slide and frame in the opposite direction, said frame and said slide being sufliciently resilient to permit insertion of said slide cross-bar within said frame by forcing said inclined strap engaging portion past said lug portion in the direction of said one frame cross-bar, said inclined plane strap engaging portion having the bottom edge thereof inturned to grip the end of a strap.

6. A slide buckle comprising, a frame having side-bars and cross-bars defining a pair of strap receiving openings therethrough to receive a strap, the edges of said frame side-bars being inturned to provide slide supporting shoulders, a slide consisting of a single cross-bar having end portions adapted for sliding movement along said shoulders and an inclined plane strap engaging portion inclined relative to said end portions for cooperation with one of said frame cross-bars to clamp in adjusted position a strap threaded through said openings, a second one of said frame cross-bars having a lug portion extending into the path of movement of said strap engaging portion to limit relative movement between said slide and said frame in one direction, said one frame cross-bar having a flanged edge extending into the path of movement of said strap engaging portion to limit relative movement of said slide and said frame in the opposite direction, a third one of said frame cross-bars acting as a strap hold-down bar and being positioned outside the path of movement of said strap engaging portion, said second cross-bar being deformable upwardly to permit insertion of said slide within said frame by sliding said slide cross-bar past said strap hold-down cross-bar and forcing the inclined plane portion thereof past said lug portion in the direction of said one frame cross-bar.

7. A slide buckle comprising, a frame having side-bars and cross-bars defining a pair of strap receiving openings therethrough to receive a strap, the edges of said frame side-bars being inturned to provide slide supporting shoulders, a slide consisting of a single cross-bar having end portions adapted for sliding movement along said shoulders and an inclined plane strap engaging portion inclined relative to said end portions for cooperation with one of said frame cross-bars to clamp in adjusted position a strap threaded through said openings, 21 second one of said frame cross-bars having a lug portion extending into the path of movement of said strap engaging portion to limit relative movement between said slide and said frame in one direction, said one frame cross-bar having a flanged edge extending into the path of movement of said strap engaging portion to limit relative movement of said slide and said frame in the opposite direction, a third one of said frame cross-bars forming a strap hold-down bar and being positioned outside the path of movement of said strap engaging portion, said second cross-bar being deformable upwardly to permit insertion of said slide within said frame by sliding said slide cross-bar past said strap hold-down cross-bar and forcing the inclined plane portion thereof past said lug portion in the direction of said frame cross-bar, said strap engaging portion having the bottom edge thereof inturned to grip the end of a strap.

8. A slide buckle comprising, a frame having side-bars and cross-bars defining a pair of strap receiving openings therethrough to receive a strap, the edges of said frame side-bars being inturned to provide slide supporting shoulders, a slide consisting of a single cross-bar having 0 end portions adapted for sliding movement along said shoulders and an inclined plane strap engaging portion inclined relative to said end portions and positioned substantially entirely below the upper surface of said end portions for cooperation with one of said frame cross-bars to clamp in adjusted position a strap threaded through said openings, a second one of said frame cross-bars having a lug portion extending into the path of movement of said strap engaging portion to limit relative movement between said slide and said frame in one direction, said one frame cross-bar having a flanged edge extending into the path of movement of said strap engaging portion to limit relative movement of said slide and said frame in the opposite direction, a third one of said frame cross-bars forming a strap hold-down bar and being positioned outside the path of movement of said strap engaging portion, said second cross-bar being deformable upwardly to permit insertion of said slide within said frame by sliding said slide crossbar past said strap hold-down cross-bar and forcing the inclined plane portion thereof past said lug portion in the direction of said one frame crossbar.

9. A slide buckle comprising, a frame having side-bars and cross-bars defining a strap receiving opening therethrough to receive a strap, said frame side-bars including side walls extending rearwardly of the face of the frame and inwardly turned slide supporting shoulders, a single cross-bar slide having end portions adapted for sliding movement along said shoulders and an intermediate strap engaging portion inclined relative to said end portions and positioned substantially entirely below the upper surface of said end portions for cooperation with one of said frame cross-bars to clamp in adjusted position a strap threaded through said opening, said one frame cross-bar having a downturned clamping edge extending into the path of movement of said strap engaging portion to limit relative movement of said slide and said frame in the forward direction, a third one of said frame cross-bars forming a strap hold down bar and being positioned outside the normal path of movement of said strap engaging portion, said slide being insertable into said frame from the rear thereof by sliding said slide cross-bar past both said strap hold down bar and said other frame cross-bar, said slide cross-bar having an inturned strap end securing portion positioned beneath and extending generally parallel to the face of said slide for clamping the end of a strap.

References (Iited in the file of this patent UNITED STATES PATENTS 

